The fabric characteristics are strongly dependent upon the characteristics of yarns. For a better fabric quality, the arn parameters like hairiness, strength, elongation, neps, uster unevenness etc. are important. In spinning process these parameters are obtained during draft operation. In the drafting arrangement, the most important factors for the yarn quality are the apron and the cot, which achieve the draft. In this research, various yarns were produced by using different types of aprons and cots. Then the yarns were tested by Uster Tester3 and Uster Tensorapid, and SPSS 10.0 for Windows were applied to the results. These results were evaluated by One-way ANOVA analyze. At the end, the effects of apron and cot types on the yarn quality were determined.